| 1 | #include <stdio.h> |
| 2 | /* |
| 3 | * fold - fold long lines for finite output devices |
| 4 | * |
| 5 | * Bill Joy UCB June 28, 1977 |
| 6 | */ |
| 7 | |
| 8 | int fold = 80; |
| 9 | |
| 10 | main(argc, argv) |
| 11 | int argc; |
| 12 | char *argv[]; |
| 13 | { |
| 14 | register c; |
| 15 | FILE *f; |
| 16 | char obuf[BUFSIZ]; |
| 17 | |
| 18 | argc--, argv++; |
| 19 | setbuf(stdout, obuf); |
| 20 | if (argc > 0 && argv[0][0] == '-') { |
| 21 | fold = 0; |
| 22 | argv[0]++; |
| 23 | while (*argv[0] >= '0' && *argv[0] <= '9') |
| 24 | fold =* 10, fold =+ *argv[0]++ - '0'; |
| 25 | if (*argv[0]) { |
| 26 | printf("Bad number for fold\n"); |
| 27 | exit(1); |
| 28 | } |
| 29 | argc--, argv++; |
| 30 | } |
| 31 | do { |
| 32 | if (argc > 0) { |
| 33 | if (freopen(argv[0], "r", stdin) == NULL) { |
| 34 | perror(argv[0]); |
| 35 | exit(1); |
| 36 | } |
| 37 | argc--, argv++; |
| 38 | } |
| 39 | for (;;) { |
| 40 | c = getc(stdin); |
| 41 | if (c == -1) |
| 42 | break; |
| 43 | putch(c); |
| 44 | } |
| 45 | } while (argc > 0); |
| 46 | exit(0); |
| 47 | } |
| 48 | |
| 49 | int col; |
| 50 | |
| 51 | putch(c) |
| 52 | register c; |
| 53 | { |
| 54 | register ncol; |
| 55 | |
| 56 | switch (c) { |
| 57 | case '\n': |
| 58 | ncol = 0; |
| 59 | break; |
| 60 | case '\t': |
| 61 | ncol = (col + 8) &~ 7; |
| 62 | break; |
| 63 | case '\b': |
| 64 | ncol = col ? col - 1 : 0; |
| 65 | break; |
| 66 | case '\r': |
| 67 | ncol = 0; |
| 68 | break; |
| 69 | default: |
| 70 | ncol = col + 1; |
| 71 | } |
| 72 | if (ncol > fold) |
| 73 | putchar('\n'), col = 0; |
| 74 | putchar(c); |
| 75 | switch (c) { |
| 76 | case '\n': |
| 77 | col = 0; |
| 78 | break; |
| 79 | case '\t': |
| 80 | col =+ 8; |
| 81 | col =& ~7; |
| 82 | break; |
| 83 | case '\b': |
| 84 | if (col) |
| 85 | col--; |
| 86 | break; |
| 87 | case '\r': |
| 88 | col = 0; |
| 89 | break; |
| 90 | default: |
| 91 | col++; |
| 92 | break; |
| 93 | } |
| 94 | } |